Blue fuel staining

[aaronk25]

Darn it blue staining is back and I have isolated it, I think to only appearing after periods of wide open throttle. I can smell a slight fuel smell when ever I move the throttle from 3/4 to wide open. I think creating more suction by reducing the throttle is stopping the leak......is this a smoking gun?????

[BigTex]

One word... bladders.

[carusoam]

Fuel aroma related to throttle position doesn't sound like "ordinary" leaky tanks.

This would be a find out what you have because you are alone....

Not trying to make you nervous, but I would want more info about what is causing the fuel aroma...

Fuel leaks related to the engine can allow air in as well as fuel out...leading to reduced or no power.

Best regards,

-a-

[aaronk25]

OK here is the deal.  This is important for all J owners.  So after long discussions with my mechanic and John Paul at GAMI (whos seen this before in J's) is that there isn't much of a pressure differnce between the intake and the outside atmosphere when at cruise speeds (ias) and the intake.  So what happens as the air coming in the front of the cowl hits the injector it creates a vaccum behind the injector which lowers the pressure just enough to allow fuel to seep out though the vent in the injector, which is supposed to help mix air with the fuel helping vaporize the fuel for more efficent combusion.  So what is happening is since there isn't any real difference in pressure the fuel is pissing out over the side of the cylinder and then dripping down the intake tubes then on to the cowl and out the cowl flap.

 

When did this start?  I think right after I installed the challenger airfilter (k&n).  I think its less restrictive which narrows the margin between intake and atmospheric pressure, when WOT.  

 

So after talking with GAMI they said close the throttle enough to lower the MP 1/4".  I have also noticed this does eliminate the staining.  Another option GAMI and I were thinking about is trying to manufacture some sort of small dam localized to the injector area to keep the cooling air from impacting the vents on the injector and yes I do realize this is forbidden without a feild approval but does anyone have any ideas how to do this?  

 

Thanks,

 

Aaron